1. Introduction. Rapid urbanization development has increased the consumption of concrete. It is estimated that the global concrete production has reached 33 billion tons annually [1].This demand for concrete requires extensive sand excavation, which impacts the environment negatively with problems such as erosion of …
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Moreover, Khatib [90] observed a declining trend of compressive strength of concrete with the increase in fine brick aggregate content in concrete. They further noticed a higher rate of long-term strength development in brick aggregate concrete after 28 days due to the pozzolanic activity of silica and alumina contents of brick in the mix.
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The porosity of an aggregate may also affect workability of concrete. If the aggregate can absorb a great deal of water, less will be available to provide workability. The particle size of coarse aggregate influences the water requirement for a given consistency (Table 1). Additionally, very fine or angular sands require more water for a given ...
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Aggregate is classified as two different types, coarse and fine. Coarse aggregate is usually greater than 4.75 mm (retained on a No. 4 sieve), while fine aggregate is less than 4.75 mm (passing the No. 4 sieve). …
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The study investigated the level of replacement of fine aggregate with waste glass that will result in optimal compressive strength. A total of 36 cubes were cast. 6 cubes without waste glass (control) and 30 cubes containing waste glass as partial replacement for fine aggregates at 15%, 25%, 35%, 45%, and 50%. Water/cement ratio of 0.6 was used.
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The results also prove the increase in the air content with the increase of fine aggregate, which is a fact that the higher percentages of fine aggregate in the mix lead to a higher permeability. Fig. 3 presents the slump flow and the flow time measured by the V-Funnel test at various ratios of fine/course aggregates. The figure shows that the ...
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If there is a deficiency in a locally available fine aggregate, concrete may benefit from the addition of air entrainment, additional cement, or a supplemental cementitious material (SCM) to address these shortcomings. Broad coarse-aggregate gradation ranges are listed in Table 2 of ASTM C 33. These broad gradation bands are for use all across ...
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A.: If the quantities of coarse aggregate, fine aggregate, cement and water are the same for both mixes, the mix with l l/2-inch aggregate will have greater slump and will probably bleed more. If both mixes are plastic the resulting strengths of the two mixes will probably be about the same. If, however, the two mixes are designed for the same ...
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The increase in the volume of a given mass of fine aggregate caused by the presence of water is known as bulking. The water forms a film over the fine aggregate particles, exerts the force of surface tension and pushes them apart increasing the …
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Various waste may be used to create fine aggregates for concrete [10,11,12,13]. Much research is focused on improving the quality of environment in different ways [14,15,16,17]. The demand for natural resources has increased along with the continuous rise in living standards, and increasingly more industrial waste is being created .
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The results also prove the increase in the air content with the increase of fine aggregate, which is a fact that the higher percentages of fine aggregate in the mix lead to a higher permeability. Fig. 3 presents the slump flow and the flow time measured by the V-Funnel test at various ratios of fine/course aggregates. The figure shows that the ...
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Because of RA's high-water absorption, they were saturated before blending in the concrete mix. Fine and coarse aggregates were used in saturated surface conditions. ... Fig. 14 (a) shows that as the amount of recycled aggregate was increased in concrete samples, the compressive strength of concrete samples was reduced after an …
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The use of copper slag as a substitute for conventional fine aggregates has shown an increase in compressive and split tensile strength, as well as flexural strength, for various concrete grades. 3. The optimal dosage level of copper slag for the M20, M40, and M60 grades of concrete is 60 percent, 50 percent, and 40 percent, respectively, based ...
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It specifies the amount of water that may be added to subtracted to the mixture. Mix design of concrete cannot be carried out …
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Sand concrete is a new type and special composite material [1,2,3], which has attracted widespread attention due to its excellent mechanical properties and low self-weight relatively.These excellent …
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Abstract. The use of recycled aggregates derived from construction and demolition wastes increased in the concrete construction industry. While the coarse fraction (i.e., from 5 to 20 mm) was successfully recycled, the fine fraction (i.e., from 0 to 5 mm) is hardly recyclable given its heterogenous nature and poor physical properties.
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Gangue fine aggregate concrete is used in concrete-filled steel tube and reinforced concrete stubs. • The increase in r G S increases the ductility of the coal GSCFST. • Constitutive model of the gangue sand concrete is proposed. • Environmental impact of the GSCFST is less than that of the RGSC.
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The results were of concrete. prepared in concrete Fines using content strength. the basic in A sand study show that, in workability mix of 1:2:4. was 2%, increased. decreased the effect of fines The workability ratio of 0.55 and the study compressive of concrete decreased strengths were and again W/C revealed on strength work that influenced ...
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Aggregate materials are a basic building block of construction and civil engineering projects. These materials, which include sand, gravel, and crushed stone, are often used in the production of concrete and asphalt, as well as for road base, fill, and other applications. However, aggregate materials have many other uses beyond their role in ...
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In this study, natural fine aggregates (NFAs) in high-strength fly ash (FA)/ground granulated blast furnace slag (GGBFS)-based geopolymer concretes were both partially and completely replaced by RFAs to prepare geopolymer recycled fine aggregate concrete (GRFC). Herein, the impacts of RFA content (0%, 25%, 50%, 75%, and ) …
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Building Materials. Coarse aggregate is one of the essential components of concrete and occupies the largest volume in the mix. That is why it greatly affects the concrete mix design. Its properties such as strength, maximum size, shape, and water absorption influence water demand, the quantity of cement and fine aggregate in concrete mixture.
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The best utilization of rubber fine aggregates in concrete was added them in the manner with content of ≤ 3.0% (about 10.0% for the volume of sand fine aggregate), in size of 2–4 mm and pretreated by 5% sodium hydroxide solution or KH-570.
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The content of PET fine aggregate is increased from 0% to 15%, and Gf is increased from 26.7 N/m to 41.1 N/m, an increase of about 54%. This can be attributed to the increased bridging effect of PET particles on the cracked surface. The feature length increases from 17.10 mm to 26.33 mm, and the brittleness of concrete decreases [102]. …
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3.2. Experimental methods3.2.1. Mix design of concrete. It should be noted that CRCA is referred to as CRCA-B before grinding and CRCA-A after grinding, while different mixtures of fine aggregates such as ' FNA', '30% FRCA+70% FNA', '60% FRCA+40% FNA' and ' FRCA' are referred to as FNA, FRCA30, FRCA60 and …
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On the other hand, the carbonation resistance is reduced with the addition of fine recycled aggregate to the concrete. Similarly Levy and Helene [18] observed that the carbonation depth decreases with the increase of recycled fine aggregate as replacement to natural aggregate. However, by using recycled aggregates, they found that the ...
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For each cement content, the four concrete mixes incorporated fine aggregate replacement ratios of 0% (control), 25%, 50%, and . The hardened concrete tests involved cubes, cylinders, and prisms. The tests addressed compressive strength, tensile strength, and modulus of rupture in accordance with the relevant ASTM standards.
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In place of fine aggregate, 0, 5, 10, 15, and 20% WFS by weight were used. • WFS was substituted for fine aggregate, which increased the durability of concrete. When 15% of the fine aggregate was substituted out for WFS, the maximum compressive strength was attained.
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The aggregates typically account about 75% of the concrete volume and play a substantial role in different concrete properties such as workability, strength, dimensional stability and durability, Conventional concrete consists of sand as fine aggregate and gravel, limestone or granite in various sizes and shapes as coarse aggregate.
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The primary component of concrete is FA. Fine aggregates play a vital role in providing the necessary workability, strength, and durability to concrete. They fill the voids between coarse aggregates and cement particles, enhancing the overall cohesion of the mixture. ... but the tensile strength of ordinary concrete increased by 96.6%. The ...
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modulus of Awotan quarry is 1.57 called fine sand. 2) The concrete compressive strength test results on Ayegun quarry specimen is. 21.33N/MM, Akufo quarry specimen is 22.44 N/MM, and Awotan quarry ...
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In order to study the flexural fatigue resistance of calcium sulfate whisker-modified recycled fine aggregate concrete (RFAC), flexural fatigue cyclic loading tests at different stress levels (0.6, 0.7, and 0.9) considering a calcium sulfate whisker (CSW) admixture as the main influencing factor were designed. Furthermore, the fatigue life was …
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The increase in the volume of a given mass of fine aggregate caused by the presence of water is known as bulking. The water forms a film over the fine aggregate particles, exerts the force of surface tension and pushes them apart increasing the volume. ... and durability of the resulting concrete. Fine aggregate particles range in size from ...
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The study shows that the workability of concrete increased from 0 to 40% at various replacement of RCA relative to the conventional concrete. ... Valcke S, Schlangen E (2021) Use of fine recycled concrete aggregates in concrete: a critical review. J Build Eng 38:102196. Google Scholar Sri R, Tam CT (1985) Properties of …
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This study investigated the mechanical behavior of normal strength (NS) and high strength (HS) concrete containing recycled fine aggregates (RFAs). A high slump mixing design was employed, which may be potentially used as filled structural concrete. The compressive strength, tensile strength, and elastic modulus were measured …
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CHAPTER 1—INTRODUCTION. Hydraulic cement concrete is a cement and water paste in which aggregate particles are embedded. Aggregate is granular material such as sand, gravel, crushed stone, blast-furnace slag, and lightweight aggregates that usually occupies approxi-mately 60 to 75% of the volume of concrete.
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However, 15% of 600µm crushed cockle shell rapidly increased and exceeded the target slump for lightweight concrete which the standard slump value was 50-75mm.
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Geiker et al. have shown that the relative yield stress and viscosity of concrete significantly increase with increased coarse aggregate (CA) volume fraction [7]. The water requirement for concrete decreases with increased aggregate particle size. Very fine aggregate requires more water for a given consistency.
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That portion of an aggregate passing the 4.75 mm sieve and predominantly retained on the 75 µm sieve is called "fine aggregate" or "sand," and larger aggregate is called "coarse aggregate". Coarse aggregate may be available in several different size groups, such as 4.7–19 mm, or 19–37.5 mm. Fine aggregates generally consist of ...
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In coarse aggregate concrete, an increase in the water-to-ash ratio (W/C) or the addition of additives or mineral additives is required to offset the lower workability of the RAC . Regarding fresh state characteristics of recycled aggregate concrete, to achieve the same target slump, both the effective and apparent w/c ratios should increase as ...
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